View Full Version : Gearing ratio for PN 70t motor

2014.10.29, 12:00 PM
I need advice on a proper gearing ratio for PN motor

2014.10.29, 01:09 PM
Depending on the size of the track I would go to a 4.40:1 for a larger track and a 4.90:1 for a tighter layout. Good jump off the corners and sufficient straight line speed. You will be flat out about 2 tiles off the corner so you can leg it at full chat down the straight as opposed to some of the more ridiculous high ratios that will get you to top speed just in time to lift for the next corner.

2014.10.29, 02:05 PM
I go way heavier. 3.8ish.
Running together with cars at 4.4 i allready have higher speed 3tiles down the straight.
Even for an 8min stint, the strain on the motor is not big enough to justify lower gearing.

2014.10.29, 02:30 PM
It also makes a big difference if you hit stuff or get stuck on the barriers. Some really aggressive gearing is fine if you're a smooth driver, if you hit stuff you should stick with something more conservative.

2014.10.30, 08:19 AM
gear to the moon with 70t try 13 pinion and 53 tooth spur at the least. When I used to run 70t I was running 14 52 without any over heating problems. Having good fets is also very important along with good batteries. Matched batteries and 4562 fets will beat handpicked motors most of the time.

2014.10.30, 09:47 AM
Since there are factors that only you are aware of I would think it wise to start in the basement and work your way up to what you are comfortable with since other determining factors and parameters are unknown to us.

In my opinion the 70T is the best all around motor offered by PN. Super reliable, easy to maintain and economical. Depending on the age of the motor you can expect to get anywhere from 20,500RPM to a touch over 30K on an older well maintained motor that has never been tampered with internally. Once they go through a couple of brush changes they loosen up and start to spool up. However, the torque curve favors lower gearing. If you don't mind spending the extra money, by all means, fill them full of "Voodoo" and burn them to the ground.

2014.10.30, 12:42 PM
Thanks for the replies guys....actually I haven't know the track size yet, this will be for PNWC Finals in Singapore mid next month, i think we will use a handout motor. I don't know much about stock 70t, my main class is always Mod (VE). Since I will be joining the race I might as well try another class just to maximise the racing experience there. I ll try around the ratio that you guys suggest and work it out slowly.

On another note, I plan to stack the fet (8858) on top of the ori (3010), will this make any improvement speedwise (70t).

2014.10.30, 03:24 PM
In 70t class, everything helps.
Better internal cabling, FETs, warm batteries, solder connections instead of screws etc

Davey G
2014.10.31, 02:52 PM
54/14, and drive it like an on off switch. :cool:

2014.11.02, 12:11 PM
I typically use 12/13t pinions depending on the layout, and fine tune with spur gear. I also raise my throttle curve to 20-50% to get on the throttle harder with less pull of the trigger.

2014.11.04, 09:28 AM
Wow! You'll be going to sg for pn's 10th anniversary PNWC cup... Cool...
If you get there early try to go to miniz sg ultimate indoor racing (formerly atomic collective) and look for Fred, he's part owner and organizer/sponsor of the races... Look for Dave Tang (one of sg' top pn sponsored drivers - he also posts on the forums here through username d1nzfe) and alvin lim... Great bunch of guys when I visited in 2013, kyosho just released the mr03ve, and it was the first day that they had it in stock!

here's the link ---> click me (http://mini-zracercom/forums/showthread.php?t=38727&highlight=Atomic+collective+Singapore) you can ask them straight what type of gearing they use...

I also believe world champ Grant and Philip will be there too... Good luck and happy racing... Would have loved to go...

Oh and here is the info of miniz sg ultimate indoor racing

Address: 11 Woodlands Close #10-01 Woodlands 11 Singapore
Contact No.: +65 86602192

2014.11.04, 10:55 AM
Yes Herman, I m going there next week. It will be my first time racing mini z abroad and possibly the biggest mini z race i will ever attending. I was hoping you can join......anyhow thanks for the info.

2014.11.04, 02:36 PM
Where are you from? And good luck! Don't forget to post pics :D

2014.11.04, 08:41 PM
I m your neighbour from Brunei.

2014.11.05, 03:45 AM
Looks like you're one out of seven drivers from Brunei...
Good luck to all the participants...